Such cutting tools are well known particularly where the cutting insert is replaceably retained by a clamping screw in an insert pocket of the cutting tool. Often with such cutting tools handling difficulties are encountered when removing or replacing the cutting insert, seeing that this requires loosening, removal and screw insertion of the clamping screw in environments in which approach to the clamping screw is either awkward or impossible. For example, in Swiss-type automatic machines cutting tools have tool shanks that are typically made of rectangular shaped bars having a cross-sectional width of between 7 and 12 mm. The cutting insert is clamped in the insert pocket either by means of a screw or a clamp. Screw clamping is disclosed in U.S. Pat. No. 5,779,400 and DE 3114460 A1. Clamps form part of a clamping mechanism that is rather bulky and are not suitable for shanks of very small cross-section. On the other hand, a problem that is encountered with screw-clamped cutting inserts in cutting tools having elongated shanks is that the screw-head is located on one side of the shank. This means that the operator, in order to loosen, remove or insert the screw has to have an approach to the side of the tool shank in which the screw-head is located, which is not always possible.